CN115910718A - Arc extinguishing system of circuit breaker and circuit breaker - Google Patents

Abstract

The invention discloses an arc extinguishing system of a circuit breaker, which comprises at least two supporting plates, at least two arc extinguishing grid pieces and at least two arc bundling plates, wherein the arc extinguishing grid pieces are arranged on the supporting plates; the arc extinguishing grid pieces are arranged at the rear part or/and the front part of the supporting plate up and down, the arc bundling plates are respectively arranged at the front part of the supporting plate, a space channel is reserved in the middle of the arc bundling plates, the height of the arc bundling plates is higher than 40% of that of the arc extinguishing system, and the arc extinguishing system provided with the arc bundling plates forms a T-shaped channel. The arc extinguishing system is provided with the T-shaped channel, the upper transverse channel is used as a pressure relief channel, and the damage to parts such as the arc extinguishing system, a shell and the like caused by overlarge arc voltage in the lower vertical channel is avoided; electric arc forms the atmospheric pressure difference from vertical passageway flow direction horizontal passageway, is favorable to electric arc to extinguish the discharge fast, and simultaneously, electric arc upward movement under the drive of air current can lead electric arc toward upper portion, improves the utilization ratio of upper portion arc extinguishing bars piece.

Description

Arc extinguishing system of circuit breaker and circuit breaker

Technical Field

The invention relates to the technical field of low-voltage electric appliances, in particular to an arc extinguishing system of a circuit breaker and the circuit breaker.

Background

In an industrial low-voltage power system, a universal circuit breaker is used as an important component in a power distribution network for distributing electric energy, connecting and breaking current in a power grid circuit and protecting lines and power supply equipment from damage caused by faults such as overload, undervoltage, short circuit, single-phase grounding and the like, and the function of breaking the overload or short-circuit current by the circuit breaker is mainly completed by an arc extinguishing system arranged in the circuit breaker. When fault current occurs in the circuit and the current value exceeds the set protection range of the circuit breaker, the tripping mechanism is driven to act, so that the movable contact and the fixed contact of the circuit breaker are quickly disconnected, and at the moment, the air medium is discharged due to the voltage between the movable contact and the fixed contact, so that high-temperature electric arc is generated. During the combustion process, the arc on the one hand causes a sharp rise in the air temperature in the arc quenching device, so that the air ionization is accelerated. On the other hand, the electric arc is divided into a plurality of short arcs by a plurality of arc separation grid pieces under the pushing of the magnetic field and the fluid effect in the arc extinguishing system, the deionization effect of the electric arc is enhanced by the metal arc separation pieces, the electric arc is reduced, the voltage is rapidly increased, and the electric arc is extinguished.

The prior arc extinguishing system technology has the following problems:

1. in the existing circuit breaker, under a higher rated working voltage, in order to ensure breaking capacity, an arc channel is compressed, and gas generating materials are arranged on two sides of a contact; because the arc channel is compressed, huge air pressure is generated during breaking, parts of an arc extinguishing system can be impacted, meanwhile, the arc is easily sprayed to the rear part of the moving contact, the arc cannot be cut and cooled quickly through the grid plate, and the arc voltage is reduced, so that the breaking failure is caused.

2. Due to the limitation of the opening distance, when the arc extinguishing system is disconnected, the moving contact cannot lead the arc to the grid sheet at the uppermost part of the arc extinguishing system, the utilization rate of the grid sheet is low, and the arc extinguishing effect voltage is greatly reduced.

3. When the arc generated during the separation between the contacts reaches the arc-extinguishing grid pieces, the arc cannot effectively contact with the arc-extinguishing grid pieces on the two sides, and the arc breaks down between the arc-extinguishing grid pieces, so that the arc voltage is reduced.

Disclosure of Invention

Based on the above background, the present invention provides an arc extinguishing system of a circuit breaker, wherein a spatial channel is left in the middle of an arc bundling plate, and the height of the spatial channel is higher than 40% of the height of the arc extinguishing system, so that the arc extinguishing system forms a T-shaped channel, and an upper horizontal channel is used as a pressure relief channel, thereby avoiding damage to parts such as the arc extinguishing system and a housing, which is caused by an excessive arc voltage in a lower vertical channel, and effectively overcoming at least one of the above problems.

The technical scheme of the invention is as follows:

in one aspect, the invention provides an arc extinguishing system of a circuit breaker, which comprises at least two supporting plates, at least two arc extinguishing grid pieces and at least two arc collecting plates; the arc extinguishing grid pieces are arranged at the rear part or/and the front part of the supporting plate up and down, the arc bundling plates are respectively arranged at the front part of the supporting plate, a space channel is reserved in the middle of the arc bundling plates, the height of the arc bundling plates is higher than 40% of that of the arc extinguishing system, and the arc extinguishing system provided with the arc bundling plates forms a T-shaped channel.

In a preferred embodiment, two arc collecting plates form a vertical channel, and the distance W2 of the vertical channel to the arc extinguishing gas outlet direction is not less than 1/3 of the length W1 of the arc extinguishing system.

In a preferred embodiment, two supporting plates form a transverse channel, the width of the transverse channel is set as W1, the width of the vertical channel is set as W2, and W1 is more than or equal to 2W2.

In a preferred embodiment, two supporting plates form a transverse channel, the height of the transverse channel is set to be H1, the height of the vertical channel is set to be H2, and H1 is less than or equal to 1/2H2.

In a preferred embodiment, the arc-chute plate is formed with a receiving cavity for receiving the leg portion of the arc-chute plate.

In a preferred embodiment, the arc bundling plate comprises a vertical plate, a top plate and a base plate, and the vertical plate, the top plate and the base plate jointly enclose to form the accommodating cavity.

In a preferred embodiment, a plurality of ribs are arranged on the base plate, and slots are formed among the plurality of ribs.

In a preferred embodiment, the leg parts of at least two arc extinguishing grid plates are mutually isolated and insulated.

In a preferred embodiment, the arc beam plate is a non-metallic material.

In a preferred embodiment, the non-metallic material is DMC, nylon, POM, JPO or epoxy glass laminate.

In a preferred embodiment, the device further comprises a cover plate and a connecting plate, wherein the top of the cover plate is provided with a vent hole, and the cover plate is detachably connected with the hole of the connecting plate through a screw.

In a preferred embodiment, the filter screen assembly further comprises a filter screen assembly, the filter screen assembly is composed of an upper filter screen plate, a lower filter screen plate, an upper cushion frame and a lower cushion frame, and the filter screen assembly is arranged between the connecting plate and the cover plate.

In another aspect, the invention further provides a circuit breaker, which includes the arc extinguishing system, the contact system, the tripping system and the operating mechanism, wherein the contact part of the contact system extends into the space channel in the middle of the arc bundling plate.

The invention has the following beneficial effects:

1. the arc extinguishing system forms a T-shaped channel, the upper transverse channel serves as a pressure relief channel, and the damage to parts such as the arc extinguishing system and the shell caused by the fact that the arc voltage in the lower vertical channel is too large is avoided.

2. The upper part and the lower part of a T-shaped channel of the arc extinguishing system form air pressure difference, and the electric arc moves upwards under the driving of the air flow, so that the electric arc can be guided to the upper part, and the utilization rate of the upper arc extinguishing grid plate is improved.

3. Electric arc is favorable to electric arc to extinguish the discharge fast from 2 passageway flow direction arc extinguishing system's of horizontal passageway and vertical passage rear portion, avoids electric arc back spray.

4. The leg parts of the arc-extinguishing grid pieces are mutually separated and insulated, so that electric arcs can be prevented from being broken down and connected in series at the leg parts of the arc-extinguishing grid pieces, meanwhile, the moving contact can be prevented from being broken down with the arc-extinguishing grid pieces at the opening position, and the arc voltage is reduced.

5. The arc bundling plate is provided with a plurality of ribs for reinforcing, so that the arc bundling plate is not easy to deform or break under high-temperature arc voltage, and the reliability of an arc channel is ensured.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic sectional structural view of an arc extinguishing system of the present invention.

Fig. 2 is a schematic perspective view of an arc extinguishing system according to the present invention.

Fig. 3 is an exploded view of the arc extinguishing system of the present invention.

Fig. 4 is a schematic structural diagram of a first arc chute of the present invention.

Fig. 5 is a schematic structural diagram of a second arc chute of the present invention.

Fig. 6 is a schematic structural view of the arc starting plate of the present invention.

Fig. 7 is a schematic structural view of an arc beam plate of the present invention.

Fig. 8 is a schematic view of the principle of the air-blow enhancement of the present invention.

Fig. 9 is a schematic diagram of the dimensions of the T-channel of the arc extinguishing system of the present invention.

FIG. 10 is a schematic view of the gas outlet structure of the arc-extinguishing chamber of the present invention.

In the figure: 2 upper cover plate, 201 upper cover plate air vent, 3 filter screen subassembly, 301 upper filter screen, 302 upper cushion frame, 303 lower cushion frame, 304 lower filter screen, 4 connecting plates, 5 screws, 6 supports, 7 first arc extinguishing bars, 703 first leg, 704 second leg, 8 second arc extinguishing bars, 803 third leg, 804 fourth leg, 9 arc convergence board, 901 base plate, 902 cover hole, slot 903, 904 top plate, 905 riser, 11 arc striking plate.

Detailed Description

Features and exemplary embodiments of various aspects of the present invention will be described in detail below. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is in no way limited to any specific configuration set forth below, but rather covers any modification, replacement or improvement of elements, parts or the like without departing from the spirit of the present invention. In the drawings and the following description, well-known structures and techniques are not shown in order to avoid unnecessarily obscuring the present invention.

As shown in fig. 1 to 10, this embodiment discloses an arc extinguishing system of a circuit breaker, including two backup pads 6 that are located the left and right sides, two arc collecting plates 9 that are located the left and right sides, arc striking plate 11, first arc extinguishing grid group, second arc extinguishing grid group that set gradually from top to bottom, first arc extinguishing grid group includes first arc extinguishing grid piece 7 of multi-disc, second arc extinguishing grid group includes multi-disc arc extinguishing grid piece 8, arc striking plate 11, first arc extinguishing grid piece 7, the both sides of second arc extinguishing grid piece 8 are passed through backup pad 6 is fixed.

First arc extinguishing bars piece 7 and second arc extinguishing bars piece 8 set up the rear portion between the backup pad 6 of the left and right sides, two anterior between the backup pad 6 that arc bundling plate 9 is located the left and right sides, two leave the space passageway in the middle of the arc bundling plate 9, the height of arc bundling plate 9 is higher than 40% of arc extinguishing system height, and the height of arc bundling plate 9 is greater than 40% promptly arc extinguishing system's height, two form the vertical passageway that has certain degree of depth between the arc bundling plate 9, two form the big transverse channel of width between the anterior upper portion of backup pad 6, vertical passageway with transverse channel is linked together, constitutes jointly arc extinguishing system's T type passageway. The distance W2 from the vertical channel to the direction of the arc extinguishing air outlet is not less than 1/3 of the length W1 of the arc extinguishing system, the width of the horizontal channel is set to be L2, the width of the vertical channel is set to be L1, and then L2 is more than or equal to 2L1; the height of the transverse channel is set to be H2, the height of the vertical channel is set to be H1, H2 is less than or equal to 1/2H1, and the vertical channel has the advantages that the opening distance of the moving contact and the static contact can be ensured by the height of the vertical channel, and electric arcs generated when the moving contact and the static contact are separated are located in the vertical channel. The T-shaped channel of the arc extinguishing system and the transverse channel on the upper portion are pressure relief channels, and damage to parts such as the arc extinguishing system and a shell caused by overlarge arc voltage in the vertical channel with the narrow lower portion is avoided.

Fig. 8 is a schematic view of the air-blowing enhancement principle of the present invention, and as shown in fig. 8, the width of the transverse channel at the upper portion of the T-shaped channel is more than 2 times the width of the vertical channel at the lower portion, so that an air pressure difference is formed between the transverse channel and the vertical channel, and the electric arc moves upwards under the driving of the air flow, so that the electric arc can be guided upwards, and the utilization rate of the upper arc-extinguishing grid plate is improved.

As shown in fig. 2, the T-shaped channel forms an upper transverse channel and a lower vertical channel, and the arc can flow to the rear part of the arc extinguishing system from the vertical channel and the 2 channels of the transverse channel, so that the arc can be extinguished and discharged quickly, and the phenomenon that the arc forms a back spray at the rear part of the arc extinguishing system is eliminated.

As shown in fig. 4 and 5, the first arc-extinguishing grid 7 and the second arc-extinguishing grid 8 are both U-shaped and have a plurality of pieces, the first arc-extinguishing grid 7 is composed of a first base, a first leg 703 and a second leg 704 which are located on both sides of the first base, the second arc-extinguishing grid 8 is composed of a second base, a third leg 803 and a fourth leg 804 which are located on both sides of the second base, the lengths of the first leg 703 and the second leg 704 are smaller than the lengths of the third leg 803 and the fourth leg 804, wherein the inner side surface of the first leg 703 and the U-shaped groove bottom of the first arc-extinguishing grid 7 form an acute angle, when the plurality of first arc-extinguishing grids 7 are stacked, the first leg 703 and the second leg 704 are adjacent in the up-down direction, the first legs 703 of the plurality of first arc-extinguishing grids 7 are stacked in a left-right staggered manner, which is beneficial to lengthening and cooling the arc voltage, when the third leg and the fourth leg of the second arc-extinguishing grid 8 are located on both sides of a compression zone, the arc-extinguishing grid can be separated from the arc-extinguishing zone, and can effectively and the arc-cooling effect can be improved.

As shown in fig. 2 and 7, the arc bundling plate 9 extends from the entrance of the vertical channel to the U-shaped groove bottom of the first arc chute 8 in the front-rear direction, the arc bundling plate 9 includes a vertical plate 905 vertically disposed on both sides of the vertical channel, a top plate 904 and a base plate 901 disposed above the vertical plate 905 and perpendicular to the vertical plate 905, the top plate 904 and the base plate 901 form a containing cavity for containing the third leg 803 and the fourth leg 804, the base plate is provided with a plurality of ribs, and a plurality of slots 903 are formed between the ribs. The substrate 901 is provided with a cover hole 902, the arc-collecting plate 9 wraps the third leg 803 and the fourth leg 804, and the plurality of ribs separate and insulate the legs 804 of the second arc-extinguishing grid 8 from each other, so that electric arcs can be prevented from being broken down and connected in series at the grid legs.

As shown in fig. 7, the arc bundling plate 9 is provided with a plurality of slots 903 for strengthening and inserting the third leg 803 and the fourth leg 804 of the second arc chute 8, so that the arc bundling plate is not easily deformed or broken under a high-temperature arc voltage, and the reliability of an arc channel is ensured.

In this embodiment, the arc bundling plate 9 is made of a non-metal material, such as DMC, nylon, POM, JPO, or epoxy glass laminate, and the nylon material is preferably used.

The arc extinguishing system of this embodiment is still including apron 2, filter screen subassembly 3 and the connecting plate 4 that is located the arc extinguishing system rear portion, filter screen subassembly 3 set up in between apron 2 and the connecting plate 4, filter screen subassembly 3 comprises last filter screen board 301, lower filter screen board 304, upper cushion frame 302 and lower cushion frame 303, air vent 201 has been seted up at the top of apron 2, just apron 2 through screw 5 with the connection can be dismantled in the hole 401 of connecting plate 4.

In the embodiment, when the moving contact and the static contact of the circuit breaker are switched on and switched off to generate electric arcs, the electric arcs are guided by the arc striking plates to pass through the T-shaped channel, enter the T-shaped channel from the electric arcs and are compressed after passing through the vertical channel, the moving speed of the electric arcs is accelerated to enter the transverse channel, and the electric arcs are cooled and discharged from the filter screen port component 3 at the tail end of the transverse channel due to the fact that the space of the transverse channel is suddenly increased, so that the electric arc extinguishing capacity is improved.

The electric arc generated by a moving contact and a static contact of the circuit breaker in the disconnection process is metal ions formed by melting the surfaces of the contacts in a free state, the metal ions, heating air around the metal ions and an electric arc bundling plate generate arc extinguishing gas clouds, the volume of the metal ions is enlarged by heating, the part of the moving contact extends into a vertical channel a1 formed by the electric arc bundling plate and provided with a narrow and compact space, when the pressure in the vertical channel a1 is increased, the pressure and the temperature of the electric arc gas clouds in the vertical channel a1 are gradually increased to form higher high-temperature and high-pressure gas, as the space at the rear part of the electric arc bundling plate is enlarged, the electric arc enters a larger space at the rear part of the electric arc bundling plate from the narrow vertical channel, a gas pressure difference is formed between the vertical channel and the larger space at the rear part of the vertical channel, the electric arc in the vertical channel rapidly enters the larger space at the rear part of the vertical channel, and the arc extinguishing grid sheet assembly rapidly cools the electric arc. Because the two legs of the arc-extinguishing grid sheet are arranged in a staggered manner, the front end of the arc striking plate is provided with the small bending angle 111, when the movable contact and the static contact are opened, the movable contact and the arc striking plate cannot interfere with each other, and the contact opening distance between the movable contact and the static contact cannot be influenced.

The structures, ratios, sizes, quantities, and the like shown in the drawings of the embodiments of the present invention are used in combination with the disclosure of the specification, so that those skilled in the art can understand and read the disclosure without limiting the conditions of the present invention, and therefore, the present invention is not limited to the practical meanings, and any modifications of the structures, changes of the ratio relationships, or adjustments of the sizes should fall within the scope of the present invention without affecting the functions and the achievable purposes of the present invention. The present embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (13)

1. An arc extinguishing system of a circuit breaker comprises at least two supporting plates, at least two arc extinguishing grid plates and at least two arc collecting plates; arc extinguishing bars piece arrange the setting from top to bottom in the rear portion of backup pad or/and front portion, electric arc bundling plate sets up respectively and leaves the space passageway in the front portion of backup pad and the centre, electric arc bundling plate highly be higher than 40% of arc extinguishing system height, its characterized in that: the arc extinguishing system provided with the arc collecting plate forms a T-shaped channel.

2. The arc extinguishing system of claim 1, wherein: two arc bundling plates form a vertical channel, and the distance W2 from the vertical channel to the direction of the arc extinguishing air outlet is not less than 1/3 of the length W1 of the arc extinguishing system.

3. The arc extinguishing system of claim 2, wherein: and two support plates form a transverse channel, the width of the transverse channel is set to be L2, the width of the vertical channel is set to be L1, and L2 is more than or equal to 2L1.

4. The arc extinguishing system of claim 2, wherein: and two support plates form a transverse channel, the height of the transverse channel is set to be H2, the height of the vertical channel is set to be H1, and H2 is less than or equal to 1/2H1.

5. The arc extinguishing system of claim 1, wherein: and the arc collecting plate is provided with an accommodating cavity for accommodating the leg part of the arc extinguishing grid plate.

6. The arc extinguishing system of claim 5, wherein: the electric arc bundling plate comprises a vertical plate, a top plate and a base plate, wherein the vertical plate, the top plate and the base plate are enclosed together to form the accommodating cavity.

7. The arc extinguishing system of claim 6, wherein: the base plate is provided with a plurality of ribs, and a plurality of slots are formed among the ribs.

8. The arc extinguishing system of claim 1, wherein: the leg parts of at least two arc extinguishing grid plates are mutually separated and insulated.

9. The arc extinguishing system of claim 1, wherein: the electric arc beam concentrating plate is made of non-metal materials.

10. The arc extinguishing system of claim 8, wherein: the non-metallic material is DMC, nylon, POM, JPO or epoxy glass laminate.

11. The arc extinguishing system of claim 1, wherein: the novel electric heating cooker further comprises a cover plate and a connecting plate, wherein the top of the cover plate is provided with an air vent, and the cover plate is detachably connected with the hole of the connecting plate through a screw.

12. The fire extinguishing system of claim 1, wherein: the filter screen assembly is composed of an upper filter screen plate, a lower filter screen plate, an upper cushion frame and a lower cushion frame, and the filter screen assembly is arranged between the connecting plate and the cover plate.

13. A circuit breaker, characterized by: comprising an arc quenching system, a contact system, a trip system and an operating mechanism according to any of claims 1-12, the contact portion of the contact system extending into a spatial channel in the middle of the arc-bundling plate.

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